prove the following trigonometric identity

Question

(sin²∅-1)/(tan²) = (1/sin²∅)-1

Answer 1

(sin²∅-1)/(tan²∅) = (1/sin²∅)-1

left side= -(1-sin²∅)/tan²∅

left side = -cos²∅/tan²∅

right side = (1/sin²∅)-1=(1-sin²∅)/sin²∅

right side = cos²∅/sin²∅=1/tan²∅

This is NOT an identity. Perhaps it needs revision.